package problem;

//镜像二叉树
public class S_101 {

    public class TreeNode {
        int val;
        TreeNode left;
        TreeNode right;
        TreeNode(int x) { val = x; }
    }

    class Solution {
        public boolean isSymmetric(TreeNode root) {
            return isMirror(root,root);
        }
        public boolean isMirror(TreeNode t1,TreeNode t2){
            if(t1==null&&t2==null) return true;
            if(t1==null||t2==null) return false;
            return (t1.val==t2.val)&&isMirror(t1.left,t2.right)&&isMirror(t1.right,t2.left);
        }
    }
}
